Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
How to find the ID wise frequency in an R data frame?
To find the ID wise frequency in an R data frame, we can use summarise function of dplyr package after defining the ID with group_by function, also the column for which we want to find the frequency will be placed inside group_by function.
Check out the below examples to understand how it can be done.
Example 1
Following snippet creates a sample data frame −
ID<-sample(1:4,20,replace=TRUE) Sales<-sample(1:10,20,replace=TRUE) df1<-data.frame(ID,Sales) df1
The following dataframe is created −
ID Sales 1 4 4 2 1 3 3 4 9 4 4 8 5 2 6 6 1 9 7 2 8 8 1 8 9 1 6 10 1 1 11 4 6 12 2 9 13 2 10 14 2 6 15 3 2 16 3 9 17 4 6 18 1 8 19 2 10 20 2 1
To load dplyr package and create an ID wise frequency column in df1, add the following code to the above snippet −
library(dplyr) df1%>%group_by(ID,Sales)%>%summarise(Frequency=n()) `summarise()` regrouping output by 'ID' (override with `.groups` argument) # A tibble: 16 x 3 # Groups: ID [4]
Output
If you execute all the above given snippets as a single program, it generates the following output −
ID Sales Frequency <int> <int> <int> 1 1 1 1 2 1 3 1 3 1 6 1 4 1 8 2 5 1 9 1 6 2 1 1 7 2 6 2 8 2 8 1 9 2 9 1 10 2 10 2 11 3 2 1 12 3 9 1 13 4 4 1 14 4 6 2 15 4 8 1 16 4 9 1
Example 2
Following snippet creates a sample data frame −
ID<-sample(0:2,20,replace=TRUE)
Group<-sample(c("I","II","III"),20,replace=TRUE)
df2<-data.frame(ID,Group)
df2The following dataframe is created −
ID Group 1 2 III 2 0 I 3 0 I 4 0 I 5 2 III 6 0 II 7 2 II 8 2 II 9 1 III 10 2 I 11 1 II 12 1 I 13 1 I 14 1 I 15 2 II 16 0 II 17 1 I 18 2 I 19 2 I 20 0 III
To create an ID wise frequency column in df2, add the following code to the above snippet −
df2%>%group_by(ID,Group)%>%summarise(Frequency=n()) `summarise()` regrouping output by 'ID' (override with `.groups` argument) # A tibble: 9 x 3 # Groups: ID [3]
Output
If you execute all the above given snippets as a single program, it generates the following output −
ID Group Frequency <int><chr> <int> 1 0 I 3 2 0 II 2 3 0 III 1 4 1 I 4 5 1 II 1 6 1 III 1 7 2 I 3 8 2 II 3 9 2 III 2
355 Views
